A STUDY OF NONSTOICHIOMETRIC OXIDES IN THE Ln-Ni-O (Ln=La, Pr, Nd) SYSTEM

Vadim Kulichenko, Sergiy Nedilko, Olexander Dziazko, Victoria Chornovol

Abstract


The non-stoichiometric compositions Ln2-xNiO4-3x/2+d (Ln=La, Pr, Nd, 0£x£0,4) were obtained using coprecipitation method from nitrates solutions by K2CO3 followed by calcination of the obtained blend at 950°С. According to X-ray phase analysis compositions in the range La2NiO4.17 – La1.6NiO3.63 are monophase and crystallize in tetragonal symmetry K2NiF4, space group I4/mmm.  Nd2-xNiO4-y  and Pr2-xNiO4-y in the range  0£x£0,2 are monophase and have orthorombic and monoclinic(correspodingly) distorted K2NiF4 structure. Samples with  0,2<x£0,4 are polyphase and contain  Ln2NiO4 (Ln=Pr, Nd), NiO and rare earth oxides. Electrical conductivity of obtained samples have semiconducting behavior and it is strong depended to nonstoichiometric oxygen content.


Keywords


coprecipitation method; non-stoichiometric compositions; nickelates; rare earth oxides; K2NiF4

Full Text:

PDF

References


Hrovat M. Characterisation of LaNi1 − xCoxO3 as a possible SOFC cathode material. Solid State Ionics 1996;83(1-2):99-105. https://doi.org/10.1016/0167-2738(95)00224-3

Zhao H, Li Q, Sun L. Ln2MO4 cathode materials for solid oxide fuel cells. Science China Chemistry 2011;54(6):898-910. https://doi.org/10.1007/s11426-011-4290-2

Lo Faro M, La Rosa D, Nicotera I, Antonucci V, Aricò A. Electrochemical investigation of a propane-fed solid oxide fuel cell based on a composite Ni–perovskite anode catalyst. Applied Catalysis B: Environmental 2009;89(1-2):49-57. https://doi.org/10.1016/j.apcatb.2008.11.019

Álvarez-Galván M, de la Peña O'Shea V, Arzamendi G, Pawelec B, Gandía L, Fierro J. Methyl ethyl ketone combustion over La-transition metal (Cr, Co, Ni, Mn) perovskites. Applied Catalysis B: Environmental 2009;92(3-4):445-453. https://doi.org/10.1016/j.apcatb.2009.09.006

BOEHM E, BASSAT J, DORDOR P, MAUVY F, GRENIER J, STEVENS P. Oxygen diffusion and transport properties in non-stoichiometric LnNiO oxides. Solid State Ionics 2005;176(37-38):2717-2725. https://doi.org/10.1016/j.ssi.2005.06.033

Schwarzenbach G, Flaschka H. Die komplexometrische Titration, Ferdinand Enke Verlag. Stuttgart: 1965.

Hoyer E. Methoden der Analyse in der Chemie, Bd. 9 Theorie und praktische Anwendung von Komplexbildnern Von F. Umland, A. Jannsen, D. Thierig und G. Wünsch; Akademische Verlagsgesellschaft Frankfurt am Main, 1971; 795 Seiten mit 22 Bildern und 34 Tabellen; Format. Z. Chem. 2010;12(10):400-400. https://doi.org/10.1002/zfch.19720121020

Přibil R. Komplexony v chemické analyse, Nakladatelství Československé Akademie Ved. Prague: 1953.

Charlot G. Les méthodes de la chimie analytique, analyse quantitative minérale, Masson et Co.: 1961.

Kulichenko VA, Nedilko SA, Dziazko AG. Visn. Kievs. Univ. Khim 1996;33:130.




DOI: https://doi.org/10.17721/fujcV3I2P89-92

Refbacks

  • There are currently no refbacks.


ISSN 2312-3222 (Online)

Creative Commons License
 French-Ukrainian Journal of Chemistry is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

Copyright (c) 2013 French-Ukrainian Journal of Chemistry